My sibling will be 28 and end by 32-33 if she goes into a Ph.D next year, but I think anyone at any age can enter a Ph.D. I've even seen a couple of 50+ year old men in undergrad when I was in college!

If people get into university at age 18, complete an undergrad in 4 years, than a masters in 2 years, then they typically complete a PhD in another 2 years. So one should usually have a PhD by the time they are 26. That varies depending on subject matter and difficulty of the research of course. But by 32, just entering a PhD is actually a little late.

No. Most folks start graduate school right after their undergraduate degree....so 21 or 22. Allow 5 or 6 years..and there you go. I would not say its unusual to be in PhD program at that age, but its not young.